You can select a Certification Programme from the list below to retrieve its description (scope of the programme, definitions...)


  See certified products

Scope of the programme

Eurovent Air to Air Rotary Heat Exchangers Certification Programme applies to all Rotary Heat Exchangers including casing.
Participants shall certify all models, if available, including:
      • all classes:
            condensation rotor / non hygroscopic
            rotor enthalpy rotor / hygroscopic rotor
            sorption rotor
      • all rotor geometry (wave height, foil thickness)
      • all sizes (rotor diameters and rotor depths and surface areas of alternating storage matrices - ASS)
      • all materials
      • all airflow rates
      • all different types of sealing (if available)

The class “sorption rotor” has to fulfill specific additional requirements on the latent efficiency (see the section "Certified Characteristics”)


Rotary Heat Exchanger:
A Rotary Heat Exchanger is a device incorporating a rotating cylinder or wheel for the purpose of transferring energy (sensible or total) from one air stream to the other. It incorporates heat transfer material, a drive mechanism, a casing or frame, and includes any seals which are provided to retard the bypassing and leakage of air from one air stream to the other.

Product Range:
The Certification Programme applies to the Rotary Heat Exchanger classes “Condensation Rotor/non hygroscopic rotor”, “Enthalpy Rotor/hygroscopic rotor” and “Sorption Rotor”.

Pressure drop:
Loss in total pressure between the inlet and the outlet of the unit within one air stream.

Face air velocity:
Velocity of air entering the unit. It shall be calculated as follow :

Wave length
Mean length of the wave (bottom).
The mean length of one wave shall be obtained from the length of the arc corresponding to 10 waves. The following formula for the arc of a circle, L, shall be used: L= D*arcsin(c/D) with L the arc of the rotor, D the diameter, and c the chord.

Wave height:
Mean height of one wave, including one flat foil thickness.

     with:   t   temperature
              11 exhaust air inlet
              12 exhaust air outlet
              21 supply air inlet
              22 supply air outlet

Humidity efficiency:
Ratio of absolute humidity differences:

Temperature efficiency:
Ratio of temperature differences:

Pressure drop:
Loss in total pressure between the inlet and the outlet of the unit within one air stream.

Exhaust Air Transfert Ratio (EATR):
Transfer of exhaust air into the supply air side in air to air regenerative heat exchanger.
EATR provides information on the level of contamination of the supply air by the exhaust air (percentage of the exhaust air in the supply air).

Outdoor Air Correction Factor (OACF):
Ration of the enterinf supply mass airflow rate and the leaving supply mass airflow rate. This parameter can be used as a correction factor for the supply air fan:
     - If OACF > 1: the outdoor air mass flow is higher than the uspply air mass flow;
     - If OACF = 1: the outdoor air mass flow equals the supply air mass flow;
     - If OACF < 1: the outdoor air mass flow is lower than the supply air mass flow.

Sorption regenerative heat exchanger:
Regenerative heat exchanger demonstrating a latent efficiency which is at least 70% of the temperature efficiency under all tested conditions with nominal airflow rate. Units having a lower humidity efficiency only can be certified as Enthalpy regenerative heat exchangers.
Testing requirements

Test standards

Performance ratings claimed by manufacturers shall be verified by tests performed in one of independent laboratory selected by ECC.

The following standards shall be used as a basis for these tests:

EN 308 (January 1997): Heat exchangers - Test procedures for establishing performance of air to air and flue gases heat recovery devices

AHRI Standard 1060 (2011): Rating air-to-air heat exchangers for energy recovery ventilation equipment.

Test specifications

Table 1: Testing conditions for sensible and latent efficiency and pressure drop

*) The Condensation units shall be tested only under the Heating condition "Regular" test conditions "Additional" conditions
Heating Cooling* Heating Cooling*
 Entering Supply Airflow Temperature 2°C 35°C -3°C  35°C  
Relative Humidity 80% 50% 90% 14.0 g/kg 22.0 g/kg 
Entering Exhaust Airflow Temperature 22°C 25°C 22°C 25°C
Relative humidity 45% 50% 11.0 g/kg 50%
Leaving Supply Airflow for rotors Face air velocity 1.5 m/s, 2.5 m/s, 4.0 m/s (3.5 if 4 is not applicable)  2.5 m/s
Leaving Supply Airflow for alternating storage systems Face air velocity 1 m/s, 1.5 m/s, 2.5 m/s 1.5 m/s
Entering Exhaust Airflow Face air velocity Same rate as 'Leaving supply airflow'
(Mass Flow Ration of 1.0)
Pressure Difference 'Leaving supply airflow static pressure' minus 'Entering exhaust airflow static pressure' 0 Pa ... 20 Pa
Rotor speed [rpm]
or damper alternate period [s]
Specified by the manufacturer
Purge configuration Specified by the manufacturer

 The following particular specifications shall be applied during the test in the independent laboratory selected by ECC:
      •  For Condensation rotors, temperature efficiency, humidity efficiency and pressure drop shall be measured under the above three "regular" Cooling and one "additional" conditions (see Table 1).
      •  For Enthalpy and Sorption rotors, temperature efficiency, humidity efficiency and pressure drop shall be measured under the above six "regular and three "additional" conditions (see Table 1).
      •  All ratings shall be performed at the rotor speed specified by the manufacturer. If an adjustable purge/cleaning sector is provided, it shall be set to the manufacturer's specified purge angle or setting. All ratings shall be performed at the same rotor speed and purge setting.
      •  The pressure drop has to be established in all tests in both air flows, for each test the average of the two measured values has to be compared with the average of the two rated values. This is to eliminate asymmetries due to the arrangement of sealing or of the purge system.

Certified characteristics

The following performance items shall be certified.

      •   Under standard conditions (20°C, 50% rel. Humidity and 1.013105Pa - or 1.20 kg/m3)

-  Airflow
-  Pressure drop
-  Outdoor Air Correction Factor
-  Exhaust Air Transfer Ratio

      •   Under "regular" winter conditions for all rotors

-  Temperature efficiency
-  Humidity efficiency

      •   Under "regular" summer conditions for Enthlapy and Sorption rotors

-  Temperature efficiency
-  Humidity efficiency

Published data

Published data correspond to following conditions :

- Rotor diameters are real outside diameters

- Air velocities are calculated according to the free face area of the rotor (inside seals and without hub) and according to a density of 1,2 kg/m3

- The nominal air flow is calculated according to the above defined velocity and a density of 1,2 kg/m³

- Pressure drop is according to a density of 1,2 kg/m³
General Reference documents

Certification Manual 15th edition (January 2019)
Reference documents


RS 8/C/002-2019